Multicomponent molecularly controlled langmuir-blodgett systems for organic photovoltaic applications

The capability of Violanthrone-79 (V-79) and N,N′-bis(2,5-di-tert-butylphenyl)-3,4:9,l0-perylenebis(dicarboximide) (PDI) to act as electron acceptors, with respect to poly(3-hexylthiophene) (PHT) and to the photoinduced fullerene anion of porphyrin−fullerene (P−F) dyad, was demonstrated in Langmuir−Blodgett (LB) films by the time-resolved Maxwell displacement charge method. The introduction of V-79 and PDI in oriented multilayered films led to improved light harvesting and increased lifetime of the charge separation, enhancing the photocurrent generation measured using a three-electrode photoelectrochemical cell. The best solar cell performance was achieved for the multifunctional film structure where efficient PHT-phthalocyanine heterojunction (PHT|ZnPH4) was combined with the P−F|V-79 system.